35 years of metallic superlattices

1

35 YEARS OF METALLIC SUPERLATTICES

DOENSF, AFOSR, ONR

IVAN K. SCHULLER

IEEE DISTINGUISHED LECTURER

IEEE Magnetics Society Home Page: www.ieeemagnetics.org– 3000 full members– 300 student members

The Society– Conference organization (INTERMAG, MMM, TMRC, etc.)– Student support for conferences– Large conference discounts for members– Graduate Student Summer Schools– Local chapter activities– Distinguished lectures

IEEE Transactions on Magnetics– ~2000 peer reviewed pages each year– Electronic access to all IEEE Transactions on Magnetics papers

Online applications for IEEE membership: www.ieee.org/join– 360,000 members – IEEE student membership IEEE full membership

The Journal of Your Field

On line at ieeexplore.ieee.orgSubmit manuscripts at mc.manuscriptcentral.com/maglet‐ieee

Peer reviewed

Rapid publication

Worldwide circulation

IEEE Xplore archive

Four‐page articles

No page charges

4

Thank you

What WE thinkof Science

6

•Boooooooooring !!!!!!!•That Is The Subject I Never Understood

In High School (College)•You Must Be Very Intelligent

What the rest of the world thinks

7

8

Bangs

Small Bangs

Big Bangs

MOST DON’T DO THIS

9

FASCINATING PHYSICSUSEFUL

YOU USE IT MILLIONS OF TIMES A DAY

10

WHY PHYSICS

11

My Start58 YEARS AGO

1957

Cluj, Kolozsvar, Clausenburg

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Lucky to Live in Chile

“Life need not be easy, provided only that it is not empty.”

Lise Meitner

Danny, Oceanographer

Jonny, Physicist

Jackie,Teacher

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Lucky to Study in Chile

14

SOMETHING FROM NOTHING

• Noether’s theoremConservation laws from philosophy

• Ginzburg-Landau 2nd order phase transitionSuperconductivity, magnetism …………………….

from series expansion

Ask fundamental questions

15

SYMMETRY

AND

CONSERVATION LAWS

Emmy Noether

16

Landau-Ginzburg

TAYLOR EXPANSION

Order Parameter: Superconducting Gap, Magnetization, Distorsion,

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18

19

CRITICAL SLOWING DOWN

TEMPERATURE

Rel

axat

ion

Tim

e (n

sec)

I. K. Schuller and K. E. Gray, PRL36, 429(1976)

20

Many Young Friends

21

22

Why do Physics

• Universal behaviorPower Laws

• New Parameters RangeSmaller

• Weird BehaviorSeparate Charge and Spin

• Big QuestionsWhat is intelligence

23

Why do Physics

• Universal behaviorPower Laws

• New Parameters RangeSmaller

• Weird BehaviorSeparate Charge and Spin

• Big QuestionsWhat is intelligence

24Z. Yang, C. Ko, and S. Ramanathan, Annu. Rev. Mater. Res. 41 (2011)

Metal-Insulator Transition

24

VO2

25338 339 340 341 342102

103

104

R (

)

T (K)

310 320 330 340 350 360101

102

103

104

R (

)

T (K)

339 340 341 342

2

4

6

R (k

)

T (K)

200 nm

Multiple jumps across the metal-

insulator transition

Nano-scale VO2R

2626

Scale Invariance

27

101 102 103

100

101

102

103

104

Num

ber o

f Jum

ps

Jump size ()

100 cycles

Statistics of Jumps

Power law: p(A) A-

p-probability A- jump size

40 80 1200

500

1000

1500

2000

Num

ber o

f Jum

ps

Jump Size ( = 2.480.05

28

Avalanches

• Triggered and develops

• Many Small avalanches

• A few big ones

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UNIVERSALITY OF

PHYSICS

30

Power Laws

M. Newman Phys. Today, P. 33 Nov. 2008

Earthquake Magnitude

Connectivity of InternetJP. Sethna et al., Nature 410, 242 (2001)

Citations (I.K. Schuller)

= 1.2

= 2.1

10 100 1000

1

10

100

Num

ber o

f Pap

ers

Number of Citations

= 1.7

31

~1.3

Sand Piles

Avalanches with Power Laws Plasma Burst (sun)

Martensites

~2.4

Barkhausen Noise

~1 - 3, depends on sand

~2.0

32

Why do Physics• Universal behavior

Power Laws

• New Parameters RangeSmaller

• Weird BehaviorSeparate Charge and Spin

• Big QuestionsWhat is intelligence

33

Nanoscience

PhysicsChemistry

CHARACTERISTIC LENGTH SCALES

34

Un homme de six pieds faitsur la terre la meme figureprecisement que fait sur uneboule de quatre pieds de circonference un animal quiserait a cette circonference de roue comme 1 est a 91 500 000

Merci Andre MagnanPresident Soc. VoltaireKVAB, U. de Nanterre

NanoBioFrench Theorist

~10nm

NANO VOLT

Francois-Marie Arouet

NANO VOLTAIRE

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SCIENCE DRIVEN RESEARCH

I.K.Schuller, Phys.Rev.Lett. 44, 1597(1980)

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MAGNETO-TRANSPORT

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~ 20 % MR

Giant MagnetoResistance- GMR

38

April, 1981

In 4 or 5 years, this will be THE fieldin materials science.

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2007 PHYSICS NOBELGrunberg Fert

GIANT MAGNETORESISTANCE

GMR

40

41

U C T )

T E

AP

PL

ICA

TIO

NS

Hard disk drives

MRAM

Sensors

SC

IEN

CE

Co

Cu

I

State: +1

State: 0

State: -1

-4 -3 -2 -1 0 1 2 3 4

-1

0

1 HFC (kOe) 0.5 2.0 5.0

M /

MS

H (kOe)

GMR SPIN TORQUE

EXCHANGEBIAS

42

Nanoscience(when things get small)

TunnelSchroedv8_1-desktop.m4v

43

e-

charge

electronics

magnetism

electron

Spin-electronicsor

Spintronics

spin

44Basic Research=Transformative Technology

45

Why do Physics• Universal behavior

Power Laws

• New Parameters RangeSmaller

• Weird BehaviorSeparate Charge and Spin

• Big QuestionsWhat is intelligence

46

THE REALCHESHIRE CAT

Went away and left behind his smile

47

FM FM

NM

I

V

NON-LOCAL SPIN VALVE

FM: ferromagnetic

NM: non-magnetic

Decouple

SPIN current from CHARGE current

I

A Crazy experiment

Valenzuela et al.,PRL 94, 196601 (2005)

48

Sample

0.5µm

1µm

FM

NM

FM

Photolithography + Au contacts

Py/Cu/Py Co/Al/Co

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-800 -600 -400 -200 0 200 400 600 800-1.0

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0I=0.5 mA

T=4.2 KPy/Cu/Py

V/|I

|(m

)

H (Oe)

-800 -600 -400 -200 0 200 400 600 800-1.0

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0I=0.5 mA

T=4.2 KPy/Cu/Py

V/|I

|(m

)

H (Oe)

-800 -600 -400 -200 0 200 400 600 800-1.0

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0I=0.5 mA

T=4.2 KPy/Cu/Py

V/|I

|(m

)

H (Oe)

-800 -600 -400 -200 0 200 400 600 800-1.0

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0I=0.5 mA

T=4.2 KPy/Cu/Py

V/|I

|(m

)

H (Oe)

Non-local spin valve effect

•Bipolar switching

• Spin signal:

IVV

IV APP

•Memory effect

50

Magnetic RAM4 Mbit chip

Revisited: 1995Demo: Motorola 2003

Market: Freescale 2006

Magnetoresistive read headDiscovery: 1988

Market: IBM 1997

Spintronics: applicationsGiant magnetoresistance (GMR)

Tunnel magnetoresistance (TMR)

51

Why do Physics• Universal behavior

Power Laws

• New Parameters RangeSmaller

• Weird BehaviorSeparate Charge and Spin

• Big QuestionsWhat is intelligence

52

11,968 processors, 12 Terabytes memory,

600 Terabytes disk storage

Jonathan Schuller6 months old

$ 200,000,000$ 30,000

53

Unifying Principlesfor

Intelligence ?Imitate Nature

“Biologically Inspired”

54

CENTRALPROCESSOR

Local processor

Local processor

Sensors Sensors

55

CENTRALPROCESSOR

SensorsSensorsLocal

processorLocal

processor

Nanoscience

CommunicationsFeedback

Wireless

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IMPLEMENTATION

Reduce to practiceImitate nature

FUNDING

58

What is needed

• Expertise- physicists, chemists, biologists, engineers• Techniques-Nanoscience, Materials, Wireless,Engineering• High Tech Facilities• Various implementations• Interactions• Steady Support

59

Organic Thin FilmsStructure, Transport, SELECTIVE Sensing

Work supported by AFOSR-MURI

PhysicsCorneliu N. Colesniuc, Amos Sharoni, Casey W. Miller, Ge Liu,

Chemistry,Richard D. Yang, Forest Bohrer ,Andy C. Kummel, William Trogler,

EngineeringJeongwon Park

60

Metallo Phthalocyanine – M C32N8H16

C

N

M = Cu, Fe, Ni, Co, ....or 2H

H

Model System for Planar Organics

61

Organic Molecular Beam Epitaxy (OMBE)

substrate

Substrate TemperatureT=30oC – 250oC

phthalocyanine

Phthalocyanine sublimes near 400oC

62

200 400 600

0.8

1.0

nor

mal

ized

cur

rent

Time (min)

small grains (25 C)m

etha

nol

met

hano

l

dosage

Bluetooth RX/TX

ChemFETMicrocontroller

Gain Amplifier

Temp & Humidity

Chemical SensorsChange Resistance

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65

DISRUPTIVE TECHNOLOGY

ARISES UNEXPECTEDLY FROM

REVOLUTIONARY BASIC SCIENCE

66

SUMMARYDo what you like,

but above all like what you do

Francisco SchullerParaphrasingLise Meitner

67

Enjoy the Process

•Caminante no hay camino, se hace el camino al andar.

Antonio Cipriano José María y Francisco de Santa Ana Machado y Ruiz

(26 July 1875 – 22 February 1939)

•Wanderer, there is no road,the road is made by walking.

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This is Why Why DoPhysics ?

69

FUTURE